It looks like something out of a science fiction movie, inside the Chernobyl exclusion zone. A former top secret military object used by the Soviet Union, the mysterious giant antenna system called the Duga-3, was the origin of an extremely powerful but anonymous signal between 1976 to 1989. The sharp, tapping signal came without warning, disrupting broadcasts and communications worldwide. Transmission power on some woodpecker transmitters was estimated to be as high as 10 MW EIRP. It was built in the 70\’s as an early missile detection system (over-the-horizon radar system). It was also called the Steel Yard hence its distinctive appearance. The towers are incredible feats of engineering: the big ones measure 479 feet tall and spans a length of 2,460 feet (nearly half a mile). The antenna was deactivated in 1989.